The ‘Konami 054574’ can be found on some PCBs from this japanese manufacturer always along with the three RGB DACs ‘054573’ (see past article for this ) so this reproduction is the natural follow up.
It shares the same SIL package and pin counting :
As well as most of the internal circuitry with open collector buffers, R/2R and transistors:
Its functions are not really clear though, for sure it’s connected to the above mentioned ‘054573’ and the ‘054338’ (which is a color mixer for special effects) so possibly it’s a RGB mixer/filter.
I simply reproduced it at ‘low-level’ identifying all the parts with their values and figured out the circuit schematics.Here’s the result .
Testing was successfully carried out on a Wild West C.O.W.Boys of Moo Mesa PCB :